The wide distribution of mobile terminals, such as mobile telephones, for example, demands fast data transmission via wireless interfaces and local wireless data networks. Light-emitting diodes (LEDs) can be used for lighting rooms in buildings. Light-emitting diodes, also referred to as LEDs, feature low energy consumption and long service life. Light-emitting diodes provided for lighting rooms inside buildings are dimmed in order to enable the luminance level within a room to be set according to the respective requirements.